Nanoimprint lithography (NIL) has been around for more than a decade. Many improvements has been made for transferring micro and nano scale structures from a stamp or template to substrates. High volume manufacturing tools for micro and nano scale pattern transfer is realized through roll-to-roll processes. This technique has been deployed in many industrial applications including medical science, microelectronics, micromechanics etc.
Obducat AB was one of the pioneers in the late nineties to commercializing Nanoimprint Lithography equipment in which they used their own technologies for transferring micro and nano scale patterns from templates to produce final product substrates, using a two-step process of imprinting. In a first step, an Intermediate Polymer Stamp (IPS) is created by imprint of a template into a polymer foil. After demolding of the IPS from the template, it is subsequently used for transferring its imprinted pattern to final substrates in a second imprint step.
In an imprint process it is very important that the imprinted foil surface, e.g. of an IPS, is protected. This is relevant both for single step imprint, where a final substrate is imprinted, and after the first imprint of a two-step process, where it is crucial that the imprinted foil stays intact until a second imprint
There are many demolding devices to detach a template, sometimes referred to as a stamp or mold, from an imprinted substrate.
US2007/0092594 A1, describes a demolding method and device to detach a mold and a substrate after imprinting process completion. In this process a blade module is inserted between the mold and the substrate, and as air is sucked into the gap and the adhesion force of vacuum effect exerting between the mold and the substrate is eliminated, the blade module is further applied to detach the mold from the substrate completely.
US2012/029992 A1 discloses full wafer nano imprint lithography. In this context, a demolding process is described using a vacuum passageway connected at the outermost sides of a mold, while applying compressed air from a demolding nozzle against the interface between mold and substrate. The pressure on the mold is gradually converted into vacuum from two sides towards the center of the mold, for continuous peel-off demolding.
U.S. Pat. No. 8,550,801, discloses an imprint apparatus for repetitive step-wise imprint on a large substrate, which includes a demolding control device. This device is configured to control the demolding speed or angle of the template based on the position of a shot region near the edge of the wafer.
US2013/0323347 A1 shows a demolding device for an imprint device. The demolding device detaches a sheet-shape mold from a molded product. The demolding device is placed away from the transfer device, i.e. the imprinting station. The process is as follows: after the transfer of the pattern at the transfer device the molded product is adhered to a sheet-shaped mold and moved to the detaching device. The molded product is placed on a molded product holder, provided with multiple vacuum holding grooves that holds the molded product by suction. In order to detach the molded product from the sheet-shaped mold a detaching roller unit moves horizontally over the holder.